Fool the BIOS booting any USB stick as a Hard Disk

1. The highest bootability (100%) of any USB stick is reached when BIOSes with USB support recognize it as a Hard Disk and then boot it in Hard Disk emulation mode.2. About the USB booting many BIOSes are not adequately featured and refuse to boot a USB stick unless it is recognized as a Hard Disk.3. Any previous way (except the rarely possible flipping of the removable bit) is not really able to recognize from the BIOS a USB stick as a Hard Disk.4. Hard Disks are the only mass storage devices that can be normally partitioned with more than 1 partition.5.The partitioning with more than 1 partition is able to fool the most BIOSes that any USB stick is a Hard Disk.6. This is the most effective and simple way to achieve the highest bootability of any USB stick.7. It might work in 100% of cases.

Preliminary Notes

A brief note about naming: as known "UFD" is the acronym of USB Flash Drive and actually it seems the official name for USB Removable Devices.http://en.wikipedia....sh_drive#Naming"Bootability" is a term that expresses the concept of hardware-compatibility matched by your UFD vs. your BIOS, so if in your BIOS setup all settings for USB booting are enabled and it fails to boot your bootable UFD then the related bootability is low.https://www.codidire...bootability.htm

Running some tests in order to increase the bootability of my USB Flash Drive I've experienced two simple ways with effective results.The following two ways are related to existing USB support in the BIOS, that's just as the most BIOSes have.Here is described what I did in order to boot any UFD from (reasonably) the most machines out there.

1.The Simplest Way, that I named Format-it-&-Forget-it.

As we all know, even if the most BIOSes are perfectly able to boot a USB Hard Disk, often they completely refuse to boot a USB Flash Drive.Some BIOSes seem to "assume" that a USB Flash Drive can not be partitioned, and on the other hands the most BIOSes seem to "acknowledge" that a USB Hard Disk can be.So, if you just create 2 partitions on your UFD then your BIOS will believe that your UFD is a USB Hard Disk just because it is partitioned, and then it will boot!

No special tweaking or physical hacking of your UFD is needed and no special tool or utility is used in order to make your UFD bootable: you only need for a filter driver, the XP's Disk Management console and a boot loader.

In order to increase the bootability of your UFD it is enough to create just 2 partitions on it.

Really it would be impossible due to the fact that Windows allows just one single partition on your UFD, but if you install a Filter Driver under your Windows PC then your UFD will become perfectly partitionable because Windows (thanks to the filter driver just installed) will recognize it like a Hard Disk (Basic Disk) and you can easily partition it using the XP's Disk Management console (Start > Run > diskmgmt.msc).Please note that XP's Disk Management console still seems the best choice in order to contribute to a high bootability, creating a MBR of your device (with the Partition Table inside) widely and reliably compatible.So, if you are planning to perform this tutorial, please do NOT use any other partitioning software.

HowTo:

1. Download "soviet_direct_hooking_src.zip" from here http://www.codeproje...ct_hooking.aspxthen unzip it and rename "dummydisk.sys" as "dummy.sys".Copy "dummy.sys" in your "system32\drivers" folder and add "dummy.reg" to the registry (with a double-click).

"dummy.reg"[codebox]color black/cyan yellow/cyantimeout 30default 0title Active@ Partition Recoverymap --mem /boot/apr.ima (fd0)map --hookchainloader (fd0)+1rootnoverify (fd0)title Linux Parted Magickernel /boot/pmagic/bzImage noapic root=/dev/ram0 init=/linuxrc keymap=us liveusb vga=791 sleep=0 quiet xvesa tmpfs_size=350M ramdisk_size=25000 directory=/bootinitrd /boot/pmagic/initrdtitle Norton Partition Magicmap --mem /boot/npm.ima (fd0)map --hookchainloader (fd0)+1rootnoverify (fd0)title Paragon Total Defragfind --set-root /boot/ptd.isomap --mem /boot/ptd.iso (hd32)map --hookchainloader (hd32)boottitle RecoverSoft Media Tools Promap --mem /boot/mtl.img (fd0)map --hookchainloader (fd0)+1rootnoverify (fd0)title Symantec Ghostmap --mem /boot/gho.ima (fd0)map --hookchainloader (fd0)+1rootnoverify (fd0)title TeraByte BootIt NGmap (hd0,0)/boot/bng.iso (hd32)map --hookchainloader (hd32)title VistaPEmap (hd0,0)/boot/vpe.iso (hd32)map --hookchainloader (hd32)title Windows XP Professionalfind --set-root /ntldrchainloader (hd0,0)/ntldr[/codebox]6. Done!You just have highly increased the bootability of your UFD.[u]Since the most BIOSes regularly support USB-HDD booting and now your UFD is seen by the BIOS as an HDD (just because you have partitioned it), then your UFD will boot not only from your PC, but also (reasonably) from the most machines out there![/u][b]2.[/b] [u]The Democratic Way[/u]: that I named [b]Format-it-&-Boot-it[/b].Since so many reports refer that the 1st partition in FAT file-system on your UFD would ensure the highest level of hardware compatibility at booting, I thought: why not just provide one?So, in order to even further increase the bootability of your UFD you have to perform the above way with some following differences.[b]HowTo[/b]:1. After installing the filter driver as described above then create the 1st partition on your UFD up to 2047 MB in size and format it in FAT file-system.2. Then create the 2nd partition of an appropriate size in FAT32 or NTFS file-system and mark it as active.Really you can create up to 4 primary partitions on your UFD, depending on your needs.[url="http://www.hostanyimage.com/"][img]http://www.hostanyimage.com/files/m6j9fynhz8udvl91356w.png[/img][/url]3. Now install "grub4dos" in the MBR of your UFD as described above and copy "grldr" and "menu.lst" in the root of the 1st partition.4. Edit your "menu.lst" file in an appropriate way, create a folder named "boot" in the root of the 1st partition (or in any other not-encrypted partition if you have created ones) of your UFD and place into it all you want to load and to select through "grub4dos" Menu screen at startup.5. Done![u]Now, since so many reports refer that the 1st partition in FAT file-system assures the highest hardware-compatibility (please, read: bootability) then you have just further increased the bootability of your UFD and it will boot (reasonably) even from more machines than performing the previous simplest way![/u]Please, note that this way you can run [u]Multiple XP[/u], as well as "Full XP in Single-Booting", "Full XP in Dual-Booting", "Full XP in Multi-Booting", [u]indifferently from the 1st, 2nd, 3rd and/or 4th Active Partition of your UFD[/u] selecting through "grub4dos" Menu screen at startup which you want to load (included all supported applications as ISO, IMA, IMG, etc, if existing); just as described in [b]Multiple XP on Multi-Partitioned USB Flash Drive[/b] here [url="http://www.boot-land.net/forums/index.php?s=&showtopic=7466&view=findpost&p=62682"]http://www.boot-land.net/forums/index.php?...ost&p=62682[/url][b]To add/replace in "menu.lst" example for Full XP in Dual-Booting[/b] (very simplified, thanks to [b]jaclaz[/b] and [b]tinybit[/b])[code]title Windows XP Professional &#40;from the 2nd partition&#41;unhide &#40;hd0,1&#41;hide &#40;hd0,2&#41;root &#40;hd0,1&#41;chainloader /ntldrtitle Windows XP Professional &#40;from the 3rd partition&#41;unhide &#40;hd0,2&#41;hide &#40;hd0,1&#41;root &#40;hd0,2&#41;chainloader /ntldr[/code]

Good luck!

The Known Background

The most relevant argument explaining why so many issues occur at the booting with USB Flash Drives seems essentially imputable to the lack of an industry-standard USB-oriented common protocol of BIOS manufacturers.Then, accepting that a full - that's a really universal - hardware-compatibility with all existing BIOSes (modern and of the past) appears as reasonably unreachable, we must seek-out for the most compatibility possible.If you take a look at the jaclaz's FAQ #10 you can discover that there are many reasons preventing the success at USB-booting.http://home.graffiti...SB/USBfaqs.htmlFurthermore if you read herehttp://www.boot-land...showtopic=6546#you can see again that a real and total compatibility with all BIOSes - even if theoretically declarable - is practically unattainable, at least following an acceptable real and known way.So we must settle for the widest-possible applicable compatibility.

Reducing too many possible variables in a reasonable number-and/or-circumstances it seems that there are at least two "easily" practicable conditions that can ensure to your USB Flash Drive a statistically high-grade of compatibility at USB-booting for a high percentage of machines (that's of BIOSes), more or less modern:1. FAT(16) file-system (as the 1st partition);2. Fixed Disk (as USB Flash Drive behaving like USB-HDD).

By the user-side all improving attempts can be made only on what we can change, but obviously (except some BIOS-related projects like "coreboot.org") on existing BIOSes we can't.

In other words: if it's true, and it seems so true, that when a booting fails any BIOS is always "guilty" while any UFD is always "innocent", then - paradoxically - we are forced to act on the innocent because we can not act on the guilty!

This fact implies that you can (almost always) implement just workarounds, not a genuine solution.

So the research of a better hardware compatibility (that's a successfully booting-couple UFD/BIOS) becomes almost exclusively USB Flash Drive related (except the few settings allowed within every BIOS setup) and it represents de facto the critical area (and then the bottle-neck, if not the nightmare) where the most procedures and the most efforts are moving in order to maximize and to optimize the results (that's to reach a wide and reliable booting).

One of the most effective, if not absolutely the most effective practice in order to walk-up the best possible booting from USB Flash Drives is related to the flipping of the "removable bit" in your physical drive (really in the dedicated controller within your drive) that will be capable to transform your USB Flash Drive just in a physical Basic Disk (that's exactly as a Hard Disk).Then, it is a solution.

Unfortunely the results of that practice are "randomized" and limited-in-number due to a missing universal-tool capable to do that job on every UFD (although some different utilities are specifically dedicated to some different UFD controllers).As alternative ways there are some other tools-&-utilities developed to format and to make bootable your UFD, and some various techniques more or less complex thought-up in order to reach the wished success at booting, but - despite this - a really wide-&-standardized compatibility at USB-booting seems still far to be reached.

As already said all reports seem to refer that the FAT(16) file-system assures a high grade of hardware-compatibility (please, read: bootability) with the most BIOSes.Unfortunely the FAT(16) file-system is not efficient, is limited in partition-size, in cluster-size, in waste of disk space and furthermore under Windows your USB Flash Drive can have just one single partition.http://www.microsoft...v.mspx?mfr=true

Then the scenario really does not appear as the most desiderable.

However, there are two Filter Drivers (Anton Bassov's "dummydisk.sys" and Hitachi Microdrive) out there that are able (by software-side) to recognize under Windows your USB Flash Drive just like a Basic Disk and then to make it perfectly partitionable.Furthermore there is a great universal Boot Loader named "grub4dos" that has been decisive in order to obtain the described results.

So my idea was simple: since the most BIOSes - oldish ones, and newish ones too - strongly prefer at USB-booting the (1st partition in) FAT file-system, why not just provide one?

About both my idea (that I already applied it in the past with a logical partition, but resulting much less versatile) and the "grub4dos + dummydisk" wonderful combine, my recent tests have been very exciting and very effective for me; so the above procedure describes how I did and what were the additional advantages that I found.

Of course I'm very interested in unknown and/or alternative ways equally and/or so widely simple-&-effective, thus if somebody knows or has been experienced similar high-bootability results following different and/or better ways please kindly report here in order to possibly redefine the State-of-the-Art about the USB Flash Drive bootability.Thank you!

Format-it-&-Forget-it Notes.

Running some tests I've discovered that the "point of view" of the BIOS does not seem the same point of view of Windows and from the point of view of the BIOS it seems no matter if the partitions on your UFD are accessible or not under Windows, because the BIOS however will recognize that your UFD is partitioned and - just for this - it will believe that your UFD is a USB Hard Disk!

So, if your BIOS supports USB-HDD feature - like the most BIOSes just do - it will be ENOUGH that your UFD is PARTITIONED - with (at least) 2 partitions - in order to induce the BIOS to BELIEVE that your UFD is just a USB Hard Disk and then it will boot (reasonably) from the most machines out there!

This way I was able to boot "Full XP" without ANY boot loader except its own (that's just "ntldr") from the active partition of my UFD on a machine that refuses to boot ANYTHING that is not as a Fixed Disk simply partitioning my UFD!

So - about the USB booting - the simple partitioning of your UFD seems to succeed EXACTLY as the flipping of removable-bit does and then the bootability of your UFD will result highly increased!

Then it could be a universal solution, with no price to pay (because few hundreds of megabytes partitioned at the end of your UFD and not accessible from every machine are NOT really a price), and it would NOT be a workaround (because the partitioning on your UFD is REAL and your BIOS will read it very well)!

A clarification is needed.Under your Windows PC you may partition your UFD as following: the 1st partition of almost ALL the size of your UFD and the 2nd SMALL partition (in any file-system) at the end of the disk (and that you will not use): this way your UFD will remain with the almost all its size available from every machine WITHOUT any filter driver installed and it does not lose any functionality; furthermore its bootability will be effectively increased because this way it will be able to boot (reasonably) from the most machines.

So, this way appears as an EFFECTIVE and contemporarely the SIMPLEST way in order to highly INCREASE your UFD bootability.

Format-it-&-Forget-it (Full XP in Single-Booting, running without any boot loader except its own "ntldr")

Format-it-&-Boot-it Notes.

I am literally enthusiastic about the synergy of "grub4dos + dummydisk" that I've experienced: "grub4dos" is GREAT and "dummydisk" is GREAT too and they together are wondeful for me: so absolutely synergistic and so absolutely effective!

Particularly - under "Full XP" running from your UFD - "dummydisk.sys" has been able to filter ON-THE-FLY the install of all NEW (so never previously recognized) and pre-partitioned USB Flash Drives without the need to PRE-RECOGNIZE them: so it has appeared as the best candidate for this job and most of all for the creation of partition's image-backups as well as UNIVERSALLY restorable without modifications (except two lines in your "boot.ini" AFTER the restoring on a different numbered partition) on every new UFD, and on every partition of your UFD you want to boot from (1st, 2nd, 3rd and/or 4th).This fact means that you will NOT need to re-create (or to modify) your partition's image-backups (or your XP installation) for every new UFD you want to use: the same backup (even of an encrypted partition) will be working for all your USB Flash Drives: also for those that you have not yet purchased!Furthermore, "dummydisk" Filter Driver can be integrate in your customized (with nLite, as an example, just as I did) XP Installation CD-ROM with the same above results, that's with a full POST-COMPATIBILITY with every new UFD, and then ensuring a high-grade of versatility.

"You cannot have your cake and eat it",then you have to pay the price of a compromise: however in my opinion it will be a (relatively) small price to pay considering the reached advantages.

The price to pay:1. Only ONE partition will be accessible under Windows when you will attach NOT FOR BOOTING (as if you boot with your UFD all its partitions will be regularly allowed) your UFD under those machines where is NOT already installed a Filter Driver.

The benefits:1. You can boot your UFD from (reasonably) the most machines with a high-grade of success: as already said now my UFD is able to boot even from a machine that refuses to boot ANYTHING that is not as a Fixed Disk!2. Simple "newbie-proof" procedure.3. No special tweaking or physical hacking of your UFD will be needed and no special tool or utility will be used in order to make your UFD bootable, neither "HP USB Disk Storage Format Tool" nor "PeToUSB" utility, nor "Lexar BootIt", nor other ones: this procedure implies both the widest (reasonable) compatibility and the simplest usage.4. You can easily "translate" your current "Windows XP Professional SP3" running from your current PC into "Full XP from your UFD" with the minimal tweaking possible.5. You can restore either your "Full XP" installation or your UFD partition's image-backups to every new UFD without ANY modification (except two lines in your "boot.ini" AFTER the restoring on a different numbered partition) and WITHOUT both to pre-install your new UFD or to create a new partition's image-backup (or to modify your XP installation).6. You can encrypt (with TrueCrypt) your UFD System Drive with no issue.7. You can restore a RAW image-backup of your UFD encrypted System Partition to every new UFD without any modification (except a quick and easy TrueCrypt "key data/volume header" restoring from its Menu screen).

Iám trying your method to make a USB flash drive bootable.
But the filter driver is not working for me.
Did the things you write,bud can not create a new partition under Disk Management (Start > Run > diskmgmt.msc)Disk
management give me not the option to delete the partition.And
make new partitions.
My system is Windows XP with SP3.Is there an other way to
make the filter driver working?

Do you mean that after filter driver installation you do not see your UFD as a Basic Disk?Have you renamed and copied "dummydisk.sys" as "dummy.sys" in your Windows PC in "system32\drivers folder?Are you sure that you've created and added "dummy.reg" in your registry and then restarted Windows?However another way exists, but in this moment I have not the time to explain it.Please, wait for tonight...

Yes,i did the things exactly as in your tutorial.
Renamed "dummydisk.sys" as "dummy.sys".placed it in Window\
system32\drivers folder.
And with notepad++ i copied the code,and named it "dummy.reg"
placed it on my desktop and double-clickt it.A confimation
was asked and confirmed it.I looked in my registerie and the
dummy file is there.So far so good,bud after restart it stil
a removable disk

An easy way to format/partition the USB, instead of the filter drivers,
is to use Puppy Linux (or gParted Linux)
gParted works to create and format multiple partitions on usb drives.
I then used it (Puppy) to copy my files aswell.

Oke,thank you for your solution.But i find out that it's not
the filter driver that makes the problem,but i think some
kind of software on my computer.I will explain,did the same thing on a older computer,and on that computer it's working.
So i have to figure out what the"conflict"is.Jaclaz point me to the right direction,so hope i will find it

i find out that it's not the filter driver that makes the problem,but i think somekind of software on my computer.I will explain,did the same thing on a older computer,and on that computer it's working.

I'm pleased to know about the topic (that's about the UFD booting) every possible related issue (even if really not too related), but I cannot know if it is "dummydisk" or any other thing that occurs in your PC (by the way in one of my configurations I have installed UltraISO Virtual Drive and "dummydisk" without any issue), then please try the following (and/or please refer about more details), so we can know if a different filter driver can result more "compatible". First uninstall "dummydisk" adding in your registry the following

and then deleting "dummy.sys" from your "system32\drivers" folder and restarting Windows.

Now download "xpfildrvr1224_320.zip" from herehttp://home.graffiti...rvr1224_320.zipor from herehttp://files.filefro...;/fileinfo.htmlthen unzip it and rename the resulting folder as "hm".Edit "cfadisk.inf" existing in that folder, deleting the whole content of [cfadisk_device] section and replacing it with the following single line: that is a great way in order to install the microdrive-filter-driver for any UFD avoiding to specify the HardwareID for every ones (thanks to cdob)

Now, if it works for you and finally you can see your UFD as a Basic Disk then you can proceed with your UFD partitioning with Disk Management, if it still does not work then try to uninstall your Virtual Drive: because if jaclaz (really a living encyclopedia!) asked you about a probably co-existence of a virtual drive then I guess (really, I'm sure... eh eh) that he knows "something" about any kind of malfunction between drive image emulators combined with other filter drivers!

Furthermore, if Hitachi Microdrive filter driver does work where "dummy.sys" does not then we could prefer the second choice under some configurations, because one of the two ones is needed just for UFD partitioning and not for other purpose (at least in this thread).So, please try this and then kindly report here your findings.Thank you!

Btw: really I've noticed that Hitachi Microdrive (although a bit more complicated in its installation) is more stable compared to "dummydisk", but I really love "dummydisk" for its very simple install (and uninstall) and most of all for its great job under Full XP from UFD!

An easy way to format/partition the USB, instead of the filter drivers,is to use Puppy Linux (or gParted Linux)gParted works to create and format multiple partitions on usb drives.I then used it (Puppy) to copy my files aswell.

Really it's not so simple.The most important thing here is your UFD booting rather than your UFD partitioned "in any way" (though the partitioning itself is essential about the topic).Also Partition Magic running from DOS is perfectly able to partition your UFD, but then it will NOT boot (as already noticed by Dietmar in the past, although about USB-HDD partitioning with PM under Windows).And as said here http://www.boot-land...?...ost&p=62936 even replacing MBR in your UFD does work about the partitioning, but then it does NOT work about the booting: so (at least until now) we are "forced" (but also it appears as a simple and effective way) to use XP's Disk Management console.

So, about your UFD booting, you have to partition your UFD with XP's Disk Management (and not with other partitioning software) in order to create a MBR (with the Partition Table inside) that then will result really very compatible at booting.Some reports refer that the MBR (that includes the partition table) created under Windows 2000 is even better, however XP's Disk Management has always done a great job and, not only in my experience, it still appears as the simplest and the more effective way.

thank you verry much for your clear,and for me,really understandeble explenation.I did the way you discribbed.and
my UDF stick is regonized as a hard drive now.Yesterday(friday)i deleted all the software i possible think that good
be a problem,bud no results.Ussed different UDF sticks to be
sure it not depend to 1 stick.bud no result.
Iám for now not sure what the problem really is bud i'am pleassed with the solution right now!
Thank you verry much again

QUOTE (Sonny @ Mar 27 2009, 01:04 PM) An easy way to format/partition the USB, instead of the filter drivers

Really it's not so simple.

online, I beg to differ.

But let me explain that I mean the partitioning itself can be done with gParted (before or after installing grub). Rather than altering your installed OS with a third party driver.Note gParted does not bother the mbr, I have tested this on a working bootable usb. I even messed up and had to move the first partition twice, after which it still booted without any issues. Nor, does it affect files/directories as it is data losseless.

Also by 'copying the files' I simply meant if you wished to place any files in the second partition (such as a second copy of PE) you could do so from within Puppy Linux aswell. Since using this method to partition will not allow access to it thru windows.

I just thought that this might be an easy way for him to get the usb partitioned since he was having trouble with the filter driver, not that you should alter the howto or anything (great job btw Thanks).

I have tried both drivers myself but still prefer to reboot from cd over installing and then uninstalling these.

Many thanks, now we know that Hitachi Microdrive seems more compatible compared to dummydisk (really I'm not too surprised by that).So if you do not plane to buid your UFD with a Full XP then Microdrive seems a better choice.At least in this thread, it has just become the preferred, and then the official Filter Driver!

In my opinion, "dummydisk" is a bit less stable, but with the GREAT feature to install/filter ON-THE-FLY every new UFD without any user-input.It's enough to handle it with a little care and it pays you with a really great job, especially in some circumstances.

Rather than altering your installed OS with a third party driver.

Really it seems no matter, in my opinion (since you have to use a filter driver for a noble reason, and AFAIK without simpler alternatives, not for sport ).If you do not like to let some traces of any software in your Windows PC (and of course I generally agree) then you can download the freeware open-source "ODIN - Open Disk Imager in a Nutshell" - as an example - from here http://odin-win.sourceforge.net/ , create an image-backup of your working partition before any undesirable software installation and then you can restore that image-backup on your now "used" partition.All in few minutes, and just what I do when needed. However "dummydisk" is easily uninstallable: it's enough to remove one registry key and one file and it will not "disturb" you more.Furthermore "dummydisk" is needed (not optional) if you plane to build some finely working configurations on your UFD running a Full XP from.

However, I understand and partially agree your point of view, but can you see mine? Here the efforts are directed towards a broad compatibility and - as already mentioned - Disk Management console under Windows XP still seems the best choice (AFAIK).Even if you have been able to boot from your machine your UFD just formatted by GParted it is not meaning that your UFD could boot from another machine, and probably it could not.Here we are talking about an increased bootability, that's about a wide-compatibility and there are many reports out there, not only my experienced issues, that refer about XP's Disk Management Console related excellence when it creates the MBR of your disk (with the Partition Table inside).

Performing my tests on USB stick bootability I use as testing-machine a Asus P5AD2-E Premium motherboard that in 2005 was very well considered."This product is the richest feature-packed motherboard we have ever tested".http://www.cdrinfo.c...ArticleId=12430This motherboard is a fine piece of hardware, but the BIOS is rather "strange" and when it attempts to boot a USB stick then it is very difficult to work: really it does not USB boot almost anything if the BIOS does not recognize it as a Hard Disk.For this reason it is appeared to me as an effective testing-machine about the USB stick booting in Hard Disk emulation mode (that's in the most reliable USB stick boot mode).Recently I have detailed the BIOS setup settings of my testing-machine.Now I remembered and re-noticed that the BIOS of my testing-machine in auto mode assumes that a USB device MUST be not larger than 530 MB and if it so then it will boot in Floppy Drive emulation mode.

So I've just procured a USB stick of 512 MB in size with 1 single partition, and I tried to boot it from my testing-machine without to perform any special procedure (only XP's Disk Management to format it and grub4dos as boot loader): and then it has perfectly booted!

On the contrary, every USB stick larger than 512 MB does not boot in any way and in any emulation mode from my testing-machine, except if the BIOS recognizes it as a Hard Disk.

So, I have thought that since a Hard Disk seems to be the only mass storage device that can be partitioned with more than 1 partition then the BIOS should assume that if any USB device is partitioned with more than 1 partition then it must be a Hard Disk.And really it seems just so!

Furthermore every USB stick of every size with its removable-bit flipped (I own two ones just so) perfectly boots even from my testing-machine because the flipping of the removable-bit (when rarely the dedicated utility is found) makes physically my USB stick exactly as a Hard Disk. http://www.911cd.net...showtopic=21850

On the other hands, with any USB stick larger than 512 MB (and without the removable-bit flipped, that's just as a USB removable device) and up to 32 GB (I've tested every size up to 32 GB) any other procedure (HP Format Tool included) in order to make it bootable from my testing-machine had failed and any USB stick will not boot in ANY way except if it has more than 1 partition.

This fact means that HP Format Tool is not really able to fool the BIOS of my testing-machine into believing that my USB stick is a Hard Disk, because then the BIOS of my testing-machine does NOT boot when a USB stick is formatted by HP Format Tool or prepared in any other procedure.

Instead, the same BIOS perfectly boots a USB stick of every size when I create more than 1 partition on it.

(tests made looong while ago)when i first tried to boot a usb stick loooongh while ago, i found out that i have to change auto to hd , since than my usb sticks boots.with hp format utility with auto enabled i guess i only get A:\ with DOS (fdd) and couldnt boot many things (couldnt remember now).

since than, when someone have problem with usb boot, i first ask him to check bios. Sadly some bioses dont have the feature to select, i guess auto remains as default with such bioses (see bios info in pdf file of Asus A7N8X-VM ).

I look forward to test your method and have very good feelings about it, but i need time , (lots of todo list for livexp + script etc )

BEAUTIFUL . i have now understood the whole point . we make double partition just to FOOL bios that it is not booting from a removable drive . .it is ONLY there to increase the probability of booting the system.

Well, I love this reply to my post. It perfectly sums up what I've described with so many words in my tutorial and it has prompted me to compile a synthesis of my findings.For the same reason I changed the topic title.

Brief Tutorial

1. The highest bootability (100%) of any USB stick is reached when BIOSes with USB support recognize it as a Hard Disk and then boot it in Hard Disk emulation mode.2. About the USB booting many BIOSes are not adequately featured and refuse to boot a USB stick unless it is recognized as a Hard Disk.3. Any previous way (except the rarely possible flipping of the removable bit) is not really able to recognize from the BIOS a USB stick as a Hard Disk.4. Hard Disks are the only mass storage devices that can be normally partitioned with more than 1 partition.5.The partitioning with more than 1 partition is able to fool the most BIOSes that any USB stick is a Hard Disk.6. This is the most effective and simple way to achieve the highest bootability of any USB stick.7. It might work in 100% of cases.